Personal care liquids (shampoo, hair conditioners and bodywash) are incredibly multifunctional materials, created with a number of performance attributes. Viscosity is a key attribute of these materials, as well as their capability to spread, lubricate and rinse-off under specifically designed conditions.
The project aims to develop protocols to distinguish liquids with similar/identical rheological profiles in the bulk, but with known microstructural, compositional or performance differences. Such protocols aim to make use of optically active molecular tags, applied to said liquids, and using optical methods to characterise the behaviour and image of such tags as these are embedded in different formulations. Fluorescence microscopy, birefringence and fluorescence lifetime can be used to develop suitable protocols to characterise complex fluids at rest, during flow, or dilution/performance conditions. Protocols devised will be aimed towards easy implementation in laboratory equipment, not necessarily limited in complexity with a bias towards low complexity and speed. One example of such molecular tags are branched copolymer responsive surfactants (BCS). BCSs can be used to stabilise oil-in-water emulsions [1,2] and to create responsive particles,[3-6] and can be tagged with rhodamine (a fluorescent dye).[4,6] BCS-stabilised emulsions self-assemble into ‘gel-like’ systems (using glucono-δ-lactone GδL) with different rheology behaviours, which will be studied in microfluidic channels at the CCI.
Unilever and The University of Liverpool currently run the Materials Innovation Factory (MIF), a multi-million-pound facility for the discovery of new materials and microstructures, hosting joint research and industrial collaborations. The Centre for Cell Imaging, (CCI) hosts state of the art capabilities on optical measurements and automated image analysis, key capabilities for this project. For example, fluorescence correlation spectroscopy expertise (used for diffusion processes in cells and in micro-rheology) and kymograph recording (microfluidics).
The two departments involved bring a mix of expertise areas in colloidal processing, rheology of complex liquids, microscopy and imaging, giving the successful applicant a unique opportunity to develop strong proficiency in a variety of technical capabilities, with a joint level of support in the MIF and CCI.
To apply please visit: https://www.liverpool.ac.uk/study/postgraduate-research/how-to-apply/
1 J. V. M. Weaver, I. Bannister, K. L. Robinson, X. Bories-Azeau, S. P. Armes, M. Smallridge and P. McKenna, Macromolecules, 2004, 37, 2395–2403.
2 J. V. M. Weaver, S. P. Rannard and A. I. Cooper, Angew. Chem., 2009, 121, 2165–2168.
3 E. García-Tuñón, S. Barg, R. Bell, J. V. M. Weaver, C. Walter, L. Goyos-Ball and E. Saiz, Angew. Chem., 2013, 52, 7805–7808.
4 E. García-Tuñón, G. C. Machado, M. Schneider, S. Barg, R. V. Bell and E. Saiz, Journal of the European Ceramic Society, 2017, 37, 199–211.
5 C. Ferraro, D. E. García-Tuñon, S. Barg, M. Miranda, N. Ni, R. Bell and E. Saiz, Journal of the European Ceramic Society, 2017, 38, 823–835.
6 G. C. Machado, D. E. García-Tuñon, R. V. Bell, M. Alini, E. Saiz and M. Peroglio, Journal of the European Ceramic Society, 2017, 38, 949–961.